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Gallium helps convert CO2 into Carbon and Oxygen

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Re: Gallium helps convert CO2 into Carbon and Oxygen

#11

Post by cletus »

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power.

This post suggests the energy cost is ~230kWh/ton.

This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral for a net output of energy.

While this is of course only in a lab and they mention "battery" one should remain skeptical (since pretty much every battery "breakthrough" is nothing more than marketing for research funding).

This may be in the paper but in this summary I didn't see anything about how the CO2 needs to be delivered. Does it need to be in a relatively pure form? What sort of preprocessing is required?

As for the capital costs, it's hard to say anything concrete here other than if silver and Gallium are catalysts, they're both relatively cheap at that scale (Gallium seems to be It's also not clear how much of each material is required.

Not to be a broken record on HN, but I've often said--and I'll repeat here--that I don't believe altruism will solve greenhouse gas emissions and global warming: it'll only be solved when it becomes economic to do so.

Another way of putting that is when the cost of carbon capture and/or non-greenhouse gas emitting energy sources is profitable, that's when you'll see change.

[1]: https://www.eia.gov/tools/faqs/faq.php?id=74&t=11

Re: Gallium helps convert CO2 into Carbon and Oxygen

#12

Post by marcosdumay »

jarenmf wrote: post #5

> 92% efficiency in converting a tonne of CO2, using just 230kWh of energy. They estimate this equates to a cost of around $100 per tonne of CO2. Not sure if this is really competitive enough. Just read recently[1][2] that EEMPA based solution can capture at a cost of $47 [1] http://netl.doe.gov/projects/files/CostAndPerformanceBaselin... [2] https://scitechdaily.com/cheaper-carbon-capture-is-on-the-wa...

Hum... You are comparing a process that separates CO2 from a gas with a process that chemically breaks CO2. Those things do not compare.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#13

Post by punnerud »

cletus wrote: post #11

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power. This post suggests the energy cost is ~230kWh/ton. This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral fo…

The cost of 230kWh is around €30 in Norway (lower during the summer), the CO2 quota price is around €60/ton.

Norway is now building pipes to pump CO2 down to the old oil wells.

Seems like it starting to get economically profitable to grab CO2 from the air and sell the quota?

Re: Gallium helps convert CO2 into Carbon and Oxygen

#14

Post by andi999 »

cletus wrote: post #11

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power. This post suggests the energy cost is ~230kWh/ton. This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral fo…

So reducing petrol demand (let's say by switching to electric cars) might reduce the economic incentives of carbon capture significantly, interesting thought.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#15

Post by WJW »

marcosdumay wrote: post #12
jarenmf wrote: post #5

> 92% efficiency in converting a tonne of CO2, using just 230kWh of energy. They estimate this equates to a cost of around $100 per tonne of CO2. Not sure if this is really competitive enough. Just read recently[1][2] that EEMPA based solution can capture at a cost of $47 [1] http://netl.doe.gov/projects/files/CostAndPerformanceBaselin... [2] https://scitechdaily.com/cheaper-carbon-capture-is-on-the-wa...

Hum... You are comparing a process that separates CO2 from a gas with a process that chemically breaks CO2. Those things do not compare.

That depends on what you are trying to achieve? Sure, the captured CO2 is still CO2, but you can put it in an empty gas field somewhere and the net effect on atmospheric CO2 (which is what we are concerned about with regards to climate change) is the same as if you had split apart the molecules.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#17

Post by wcoenen »

s_Hogg wrote: post #9

How much of the cost is the energy? Would hooking it up to a wind turbine help?

The article says 230 kWh per ton of CO2, so you can just multiply that by a cost per kWh, e.g. 0.07 $/kWh for industry in the US.

230 * 0.07 = 16.1 dollars.

So that suggests that most of the cost is not energy.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#18

Post by flexie »

WithinReason wrote: post #10
jarenmf wrote: post #5

> 92% efficiency in converting a tonne of CO2, using just 230kWh of energy. They estimate this equates to a cost of around $100 per tonne of CO2. Not sure if this is really competitive enough. Just read recently[1][2] that EEMPA based solution can capture at a cost of $47 [1] http://netl.doe.gov/projects/files/CostAndPerformanceBaselin... [2] https://scitechdaily.com/cheaper-carbon-capture-is-on-the-wa...

Assuming 16 tons per person per year emissions [0], you can offset 1 person's carbon footprint for $1600 per year. [0]: https://astralcodexten.substack.com/p/carbon-costs-quantifie...

Every American uses around 400 gallons of gasoline and 12,000 kwh electricity per year. So if you put a tax of $2 on each gallon of gasoline and 7 cent on every kwh electricity, you would finance that.

And once it scales, it will be cheaper and cheaper, jut like most other products. With a 10 percent price reduction per year, it would be $620 per person in 10 years, roughly the same as an internet bill.

In the rest of the world it's even cheaper. The average person in the world could be offset for $400 now.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#19

Post by adrian_b »

cletus wrote: post #11

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power. This post suggests the energy cost is ~230kWh/ton. This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral fo…

"how the CO2 needs to be delivered":

The experiments described in the paper have used pure CO2. The conversion process is unlikely to work directly with air, because it decomposes CO2 into solid carbon partially oxidated and dioxygen.

If one of the products of the catalyzed reaction, i.e. oxygen from the air, would be present in a much larger concentration than the input substance (CO2), like in the air, the conversion reaction will either stop completely or it will be at least slowed down a lot.

So besides the costs for the energy and for renewing the silver and gallium from time to time and also for the organic solvents that might also need to be replaced from time to time, the cost of separating CO2 from the air must be added.

Nevertheless, it might still eventually be cheaper than alternative methods, as most of them also need to first separate the CO2 from the air.

In any case, much more research is needed to scale this from experiments in minute quantities to industrial dimensions.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#20

Post by londons_explore »

punnerud wrote: post #13
cletus wrote: post #11

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power. This post suggests the energy cost is ~230kWh/ton. This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral fo…

The cost of 230kWh is around €30 in Norway (lower during the summer), the CO2 quota price is around €60/ton. Norway is now building pipes to pump CO2 down to the old oil wells. Seems like it starting to get economically profitable to grab CO2 from the air and sell the quota?

> Norway is now building pipes to pump CO2 down to the old oil wells.

You should know that injecting old oil wells with CO2 helps them produce more oil. The CO2 becomes carbonic acid under pressure, which then dissolves pores in the rock wider, allowing more oil and gas to escape.

Also, it looks pretty doubtful that CO2 will stay in gas wells for a long time. Eventually it'll find some fissure and due to the acidity any crack will be eroded wider till all the CO2 comes out like a fizzy drink.

But don't worry. Oil and gas companies will happily collect government subsidies for pumping CO2 underground to get more oil out to sell, in the knowledge that when the gas escapes in a few decades they can act all surprised...

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